The invention relates to an input stage of an ignition control circuit for producing an output signal by using a comparator, in which the primary current of an ignition coil is switched on and off by the output signal in dependence on a control signal supplied to the input stage.
These input stages for ignition control circuits are required in particular for ignition of the engines of motorised vehicles. The ignition coil delivers the ignition spark for the engine cylinders under time control. In the past this ignition process was controlled by mechanically actuated electrical contacts but increasingly there has been a change over to using electronic ignition systems which ensure that the ignition coils are only subjected to the charging process during that period of time which is required to build up the ignition energy. As a result there is a considerable saving in energy.